CAR039 Comprehensive Lipid Profile Testing in the Evaluation of ...

In summary, the ATP III guidelines do not recommend apo A-1 for routine risk assessment, apo E is not
addressed in the guideline, and non-HDL serves as a surrogate for apo B. However, emerging data
suggest that non-HDL and Apo B are highly correlated but only moderately concordant, apo B should
therefore be used to guide adjustments to therapy in patients with residual cardiometabolic risk already
on pharmacologic treatment.
B. hs-CRP. High sensitivity C-reactive protein is a nonspecific reflection of a broad range of diverse
pathologic processes. Hs-CRP levels correlate with multiple metabolic risk factors: the more risk
factors, the higher the hs-CRP. In a study of 14,719 apparently healthy women followed for 8 years, it
was found that at baseline, median hs-CRP levels with 0, 1, 2, 3, 4, or 5 characteristics of the metabolic
syndrome were 0.68, 1.09, 1.93, 3.01, 3.88, and 5.75 mg/L, respectively (p (trend) 20% Framingham 10 year risk score), measuring CRP level would not be indicated because the
initiation of lipid-lowering therapy is clearly indicated. The AHA/CDC panel considered
recommending more widespread testing of CRP level, such as for those with a family history of CHD
or the metabolic syndrome, but considered the evidence inadequate at this time.
C. Homocysteine is an amino acid found in the body. Its role in vascular disease was spurred by the
observation that over 50% of children with the genetic disorder homocysteinuria die of premature
vascular disease. It was later proposed that individuals with severe homocysteinemia develop
premature vascular injury and atherosclerosis. Some authors therefore favor measuring homocysteine
levels with the aim of treating with supplemental vitamins. Other authors have reported that routine
testing is not recommended and it is not known if lowering homocysteine levels will reduce
cardiovascular morbidity and mortality. The ATP III does not recommend routine measurement of
homocysteine as part of risk assessment to modify LDL-cholesterol goal for primary prevention,
however, measurement remains an option in selected cases (e.g. with a strong family history of
premature CHD in an otherwise low risk patient). The SEARCH collaborative group, a double-blind
randomized clinical trials (RCT) evaluated the potential benefits and hazards of lowering
homocysteine with folic acid and vitamin B12 supplementation in 12,064 survivors of an MI and
reported that in high risk patients, supplementation did not have beneficial effects on major coronary
events. A 2009 Cochrane review that included data from eight RCTs – CHAOS, FOLARDA, GOES,
HOPE-2, NORVIT, VISP, WAFACS, and WENBIT - assessed the effects of homocysteine lowering for
preventing cardiovascular events. It concluded that homocysteine lowering did not reduce the risk of
nonfatal or fatal MI, stroke, or death from any cause.
D. Kinesin-like protein 6 (KIF6) is a member of a family of molecular motors involved in intracellular
transport of protein complexes, membrane organelles, and messenger RNA along microtubules.
Observational studies such as ARIC and WHS demonstrated a modest increase in risk of CAD in
carriers of the common KIF6719Arg variant allele. The PROVE IT-TIMI 22 trial demonstrated that
intensive statin therapy provided significantly greater benefit in KIF6 carriers than non-carriers.
Comprehensive Lipid Profile Testing in the Evaluation of Cardiovascular Disease Page 8 of 14